Abstract:

An information storage medium including two or more recording layers to
reproduce or record data by using a same reproducing and/or recording
optical system per layer includes error correction code (ECC) blocks
recorded onto the two or more recording layers by using two or more data
formats used to store user data.

Claims:

1. An information storage medium comprising two or more recording layers
on which data is recorded on and/or reproduced from by using a same
recording and/or reproducing optical system for each of the two or more
recording layers, wherein error correction code (ECC) blocks are recorded
onto the two or more recording layers by using two or more data formats
used to store user data.

2. The information storage medium of claim 1, wherein an ECC block is
recorded onto a recording layer having a cover layer with a first
thickness by using a data format from among the two or more data formats
that has a first error correction performance, and an ECC block is
recorded onto another recording layer having another cover layer with a
second thickness which is thinner than the first thickness by using a
data format from among the two or more data formats that has a second
error correction performance which is relatively high compared to the
first error correction performance.

3. The information storage medium of claim 1, wherein each of the two or
more recording layers comprises a disc management information area
separate from a data area in which the user data is recorded, onto which
at least one of the ECC blocks are recorded by using the same data format
for each of the disc management information areas.

4. The information storage medium of claim 1, wherein first replacement
data for replacing first user data of a first type ECC block having a
first data format by performing a defect management operation or a
logical overwrite (LOW) operation is stored onto the first type ECC block
having the first data format, and second replacement data for replacing
second user data of a second type ECC block having a second data format
by performing the defect management operation or the LOW operation is
stored onto the second type ECC block having the second data format.

5. The information storage medium of claim 4, further comprising:a first
spare area formed in one of the recording layers onto which the first
type ECC block is recorded and having the first replacement data of the
first type ECC block recorded thereon; anda second spare area formed in a
another one of the recording layers onto which the second type ECC block
is recorded and having the second replacement data of the second type ECC
block recorded thereon.

6. A method of recording data onto an information storage medium including
two or more recording layers to reproduce or record the data by using a
same reproducing and/or recording optical system per layer, the method
comprising:recording ECC blocks onto the two or more recording layers by
using two or more data formats used to store user data.

7. The method of claim 6, wherein the recording of the ECC blocks further
comprises:recording one of the ECC blocks onto one of the recording
layers having a cover layer with a first thickness by using one of the
data formats which has a first error correction performance, and
recording another one of the ECC blocks onto another one of the recording
layers having another cover layer with a second thickness which is
thinner than the first thickness by using another one of the data formats
having a second error correction performance which is relatively high
compared to the first error correction performance.

8. The method of claim 6, wherein each recording layer comprises a disc
management information area, and the recording of the ECC blocks further
comprises:recording the ECC blocks onto the disc management information
area of each recording layer by using the same data format.

9. The method of claim 6, wherein the recording of the ECC blocks further
comprises:storing first replacement data for replacing first user data of
a first type ECC block having a first data format by performing a defect
management operation or a logical overwrite (LOW) operation onto the
first type ECC block having the first data format; andstoring second
replacement data for replacing second user data of a second type ECC
block having a second data format by performing the defect management
operation or the LOW operation onto the second type ECC block having the
second data format.

10. The method of claim 9, wherein the recording of the ECC blocks further
comprises:recording the first replacement data onto a first spare area of
the information storage medium and recording the second replacement data
onto a second spare area of the information storage medium that is
separate from the first spare area.

11. An apparatus to record data onto an information storage medium
including two or more recording layers to reproduce or record the data by
using a same reproducing and/or recording optical system per layer, the
apparatus comprising:a recording unit to record the data onto the
information storage medium; anda controller to control the recording unit
to record ECC blocks onto the two or more recording layers by using two
or more data formats used to store user data.

12. The apparatus of claim 11, wherein the controller controls the
recording unit to record one of the ECC blocks onto a recording layer
having a cover layer with a first thickness by using one of the data
formats having a first error correction performance, and to record
another one of the ECC blocks onto another one of the recording layers
having another cover layer with a second thickness which is thinner than
the first thickness by using another one of the data formats having a
second error correction performance which is relatively high compared to
the first error correction performance.

13. The apparatus of claim 11, wherein each recording layer comprises a
disc management information area, the controller controls the recording
unit to record at least one of the ECC blocks onto the disc management
information area of each respective recording layer by using the same
data format.

14. The apparatus of claim 11, wherein the controller controls the
recording unit to store first replacement data for replacing first user
data of a first type ECC block having a first data format by performing a
defect management operation or a logical overwrite (LOW) operation onto
the first type ECC block having the first data format, and to store
second replacement data for replacing second user data of a second type
ECC block having a second data format by performing the defect management
operation or the LOW operation onto the second type ECC block having the
second data format.

15. The apparatus of claim 14, wherein the controller controls the
recording unit to record the first replacement data onto a first spare
area of the information storage medium and the second replacement data
onto a second spare area of the information storage medium that is
separate from the first spare area.

16. A method of reproducing data from an information storage medium
including two or more recording layers to reproduce or record the data by
using a same reproducing and/or recording optical system per layer, the
method comprising:reproducing ECC blocks from the two or more recording
layers by using two or more data formats used to store user data.

17. The method of claim 16, wherein the reproducing of the ECC blocks
further comprises:reproducing one of the ECC blocks from a recording
layer having a cover layer with a first thickness by using one of the
data formats having a first error correction performance, and reproducing
another one of the ECC blocks from another recording layer having another
cover layer with a second thickness which is thinner than the first
thickness by using another one of the data formats having a second error
correction performance which is relatively high compared to the first
error correction performance.

18. The method of claim 16, wherein each recording layer comprises a disc
management information area, and the reproducing of the ECC blocks
further comprises:reproducing the ECC blocks from the disc management
information area of each recording layer by using the same data format.

19. The method of claim 16, wherein the reproducing of the ECC blocks
further comprises:reading first replacement data for replacing first user
data of a first type ECC block having a first data format by performing a
defect management operation or a logical overwrite (LOW) operation from
the first type ECC block having the first data format; andreading second
replacement data for replacing second user data of a second type ECC
block having a second data format by performing the defect management
operation or the LOW operation from the second type ECC block having the
second data format.

20. The method of claim 19, wherein the reproducing of the ECC blocks
further comprises:reproducing the first replacement data from a first
spare area of the information storage medium and reproducing the second
replacement data from a second spare area of the information storage
medium that is separate from the first spare area.

21. An apparatus to reproduce data from an information storage medium
including two or more recording layers to reproduce or record the data by
using a same reproducing and/or recording optical system per layer, the
apparatus comprising:a reproducing unit to reproduce the data from the
information storage medium; anda controller to control the reproducing
unit to reproduce ECC blocks from the two or more recording layers by
using two or more data formats used to store user data.

22. The apparatus of claim 21, wherein the controller controls the
reproducing unit to reproduce one of the ECC blocks from a recording
layer having a cover layer with a first thickness by using one of the
data formats having a first error correction performance, and to
reproduce another one of the ECC blocks from another recording layer
having another cover layer with a second thickness which is less than the
first thickness by using another one of the data formats having a second
error correction performance which is relatively high compared to the
first error error correction performance.

23. The apparatus of claim 21, wherein each recording layer comprises a
disc management information area, and the controller controls the
reproducing unit to reproduce at least one the ECC blocks respectively
recorded in each of the disc management information areas of each
recording layer by using the same data format.

24. The apparatus of claim 21, wherein the controller controls the
reproducing unit to read first replacement data for replacing first user
data of a first type ECC block having a first data format by performing a
defect management operation or a logical overwrite (LOW) operation from
the first type ECC block having the first data format, and to read second
replacement data for replacing second user data of a second type ECC
block having a second data format by performing the defect management
operation or the LOW operation from the second type ECC block having the
second data format.

25. The apparatus of claim 24, wherein the controller controls the
reproducing unit to reproduce the first replacement data from a first
spare area of the information storage medium and the second replacement
data from a second spare area of the information storage medium that is
separate from the first spare area.

26. A method of recording data onto an information storage medium, the
method comprising:recording error correction code (ECC) blocks on
respective recording layers of the information storage medium, wherein a
ratio of user data to additional information used to record and/or
reproduce the user data and included within each ECC block varies
according to thicknesses of cover layers respectively corresponding to
each of the recording layers.

27. The method of claim 26, wherein an amount of the additional
information increases relative to an amount of the user data as the
thickness of the cover layer decreases.

29. A method of reproducing data from an information storage medium, the
method comprising:reproducing error correction code (ECC) blocks from
respective recording layers of the information storage medium, wherein a
ratio of user data to additional information used to record and/or
reproduce the user data and included within each ECC block varies
according to thicknesses of cover layers respectively corresponding to
each of the recording layers.

30. The method of claim 29, wherein an amount of the additional
information increases relative to an amount of the user data as the
thickness of the cover layer decreases.

Description:

[0001]This application claims the benefit of Korean Patent Application No.
2007-113720, filed Nov. 8, 2007 in the Korean Intellectual Property
Office, the disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

[0002]1. Field of the Invention

[0003]Aspects of the present invention relate to a recording and/or
reproducing method, a recording and/or reproducing apparatus, and an
information storage medium therefor, and more particularly to a recording
and/or reproducing method and a recording and/or reproducing apparatus to
reduce a drop in data reliability or a reduction in data capacity due to
different signal qualities of each layer of a multilayer information
storage medium, and an information storage medium therefor.

[0004]2. Description of the Related Art

[0005]The development of high-capacity information storage media has
resulted in active progress being made in the development of high-density
multilayer information storage media. Discs of optical systems include
cover layers in order to protect recording layers. The cover layers of
multilayer discs are disposed between disc surfaces and recording layers.
The thickness of cover layers of CDs, DVDs, and blu-ray DVDs (BDs) is 1.2
mm, 0.6 mm, and 0.1 mm, respectively. The greater the thickness of the
cover layers, the higher the density of information that can be stored in
the storage media. Cover layers of multilayer discs correspond to the
multiple recording layers of the disc. The thicknesses of the cover
layers vary according to a number of the recording layers. Therefore, a
spot area where a light beam contacts a disc surface through an object
lens varies according to a number of the recording layers. In 4, 8, and
16 multilayer discs, differences between minimum areas and maximum areas
where the light beam contacts the disc surface must be increased.
Therefore, the influence of dust particles on the light beam used to
record and/or reproduce data to and or from the optical disc varies
according to a number of recording layers. The degree of the variation is
proportional to the number of recording layers. Thus, a method to
overcome an error influence caused by dust, for each layer of multilayer
discs, is needed.

[0006]FIG. 1 is a diagram to explain a difference in a spot area of each
layer in accordance with different thicknesses of cover layers according
to conventional technology. Referring to FIG. 1, since the thicknesses of
cover layers vary according to a number of recording layers used in the
disc, a spot area where a light beam contacts disc surfaces through an
object lens varies according to a number of recording layers. That is, a
spot area 2 of a cover layer 2 having a smaller thickness than a cover
layer 1 is smaller than a spot area 1 of the cover layer 1, and the spot
area 1 of the cover layer 1, which is a combination of the cover layer 2
and an additional cover layer between layer 2 and layer 1 and has a
greater thickness than the cover layer 2, is greater than the spot area 2
of the cover layer 2. Thus, since a beam that is reflected by dust is
blocked before reaching the target layer, the beam has a different degree
of reflection by the dust according to a number of the recording layers.
That is, the reflection amount of the beam is proportional to a "spot
area"--an "area of the beam that is not incident/reflected by dust".
However, the "area of the beam that is not incident/reflected by dust"
particles having the same size on a disc surface remains constant
according to recording layers, whereas the "spot area" changes due to a
different thickness of each cover layer according to recording layers.

[0007]Although a multilayer disc has a different error influence per layer
due to a defect factor such as the same-sized dust particles,
fingerprints, scratches, bubbles, and the like on the disc surface since
cover layers have different thicknesses according to a number of
recording layers, a conventional application of the same data format
irrespective of a recording layer causes the following problem.

[0008]If a data format is based on a recording layer that is least
influenced by a defect factor according to data capacity, data
reliability is subject to a recording layer that is most influenced by
the defect factor. Thus, a disc lifetime is reduced.

[0009]Furthermore, if the data format is based on the recording layer that
is most influenced by the defect factor in order to compensate for the
data reliability, the amount of additional information used to correct an
error that occurs in a disc relatively increases, causing a reduction in
the data capacity.

[0010]For example, in a four-layer disc, first and second layers have a
similar error influence by a defect factor such as dust on the first and
second layers, whereas third and fourth layers have a double error
influence by the same defect factor as in the first and second layers. A
data format suitable for the first and second layers causes a drop in
data reliability of the third and fourth layers. A data format suitable
for the third and fourth layers that are relatively vulnerable to the
error influence causes an increase in additional information of the first
and second layers, which reduces data capacity.

[0011]A data format is generally formed of user data and additional
information. The user data is referred to as information that is to be
substantially stored. The additional information is referred to as
information, other than the information that is substantially stored,
which is necessary for recording and the substantially stored information
onto a disc or reproducing the substantially stored information. The user
data is generally scrambled or modulated before being recorded/stored
onto the disc. Examples of the additional information include sync
information, address information, and parity information of a general
optical system. The additional information according to an aspect of the
present invention may hereinafter be referred to as the parity
information.

SUMMARY OF THE INVENTION

[0012]Aspects of the present invention provide a recording and/or
reproducing method, and a recording and/or reproducing apparatus to
reduce a drop in data reliability or a reduction in data capacity due to
different signal qualities of each layer of a multilayer information
storage medium, and an information storage medium therefor.

[0013]According to an aspect of the present invention, an information
storage medium includes two or more recording layers on which data is
recorded on and/or reproduced from by using a same recording and/or
reproducing optical system for each of the two or more recording layers,
wherein error correction code (ECC) blocks are recorded onto the two or
more recording layers by using two or more data formats used to store
user data.

[0014]According to an aspect of the present invention, an ECC block may be
recorded onto a recording layer having a cover layer with a first
thickness by using a data format from among the two or more data formats
that has a first error correction performance, and an ECC block may be
recorded onto another recording layer having another cover layer by using
a data format from among the two or more data formats that has a second
error correction performance which is relatively high compared to the
first error correction performance.

[0015]According to an aspect of the present invention, each of the two or
more recording layers include a disc management information area separate
from a data area in which the user data is recorded, onto which at least
one of the ECC blocks is recorded by using the same data format for each
of the disc management information areas.

[0016]According to an aspect of the present invention, first replacement
data for replacing first user data of a first type ECC having a first
data format by performing a defect management operation or a logical
overwrite (LOW) operation is stored onto the first type ECC block having
the first data format, and second replacement data for replacing second
user data of a second type ECC block having a second data format by
performing the defect management operation or the LOW operation is stored
onto the second type ECC block having the second data format.

[0017]According to an aspect of the present invention, the information
storage medium further comprises a first spare area formed in one of the
recording layers onto which the first type ECC block is recorded and
having the first replacement data of the first type ECC block recorded
thereon, and a second spare area formed in a another one of the recording
layers onto which the second type ECC block is recorded and having the
second replacement data of the second type ECC block recorded thereon.

[0018]According to another aspect of the present invention, a method of
recording data onto an information storage medium including two or more
recording layers to reproduce or record the data by using a same
reproducing and/or recording optical system per layer, includes recording
ECC blocks onto the two or more recording layers by using two or more
data formats used to store user data.

[0019]According to an aspect of the present invention, the recording of
the ECC blocks further includes recording one of the ECC blocks onto one
of the recording layers having a cover layer with a first thickness by
using one of the data formats which has a first error correction
performance, and recording another one of the ECC blocks onto another one
of the recording layers having another cover layer with a second
thickness which is thinner than the first thickness by using another one
of the data formats having a second error correction performance which is
relatively high compared to the first error correction performance.

[0020]According to an aspect of the present invention, each recording
layer includes a disc management information area, and the recording of
the ECC blocks further includes recording the ECC blocks onto the disc
management information area of each recording layer by using the same
data format.

[0021]According to an aspect of the present invention, the recording of
the ECC blocks further comprises storing first replacement data for
replacing first user data of a first type ECC block having a first data
format by performing a defect management operation or a logical overwrite
(LOW) operation onto the first type ECC block having the first data
format and storing second replacement data for replacing second user data
of a second type ECC block having a second data format by performing the
defect management operation or the LOW operation onto the second type ECC
block having the second data format.

[0022]According to an aspect of the present invention, the recording of
the ECC blocks further includes recording the first replacement data onto
a first spare area of the information storage medium and recording the
second replacement data onto a second spare area of the information
storage medium that is separate from the first spare area.

[0023]According to another aspect of the present invention, an apparatus
to record data onto an information storage medium including two or more
recording layers to reproduce or record the data by using a same
reproducing and/or recording optical system per layer, includes a
recording unit to record the data onto the information storage medium,
and a controller to control the recording unit to record ECC blocks onto
the two or more recording layers by using two or more data formats used
to store user data.

[0024]According to another aspect of the present invention, a method of
reproducing data from an information storage medium including two or more
recording layers to reproduce or record the data by using a same
reproducing and/or recording optical system per layer includes
reproducing ECC blocks from the two or more recording layers by using two
or more data formats used to store user data, and reproducing the ECC
blocks by using the two or more data formats.

[0025]According to another aspect of the present invention, the
reproducing of the ECC blocks further includes reproducing one of the ECC
blocks from a recording layer having a cover layer with a first thickness
by using one of the data formats having a first error correction
performance, and reproducing another one of the ECC blocks from another
recording layer having another cover layer with a thickness which is
thinner than the first thickness by using another one of the data formats
having a second error correction performance which is relatively high
compared to the first error correction performance.

[0026]According to another aspect of the present invention, each recording
layer includes a disc management information area, and the reproducing of
the ECC blocks further includes reproducing the ECC blocks from the disc
management information area of each recording layer by using the same
data format.

[0027]According to an aspect of the present invention, the reproducing of
the ECC blocks comprises reading first replacement data for replacing
first user data of a first type ECC block having a first data format by
performing a defect management operation or a logical overwrite (LOW)
operation from the first type ECC block having the first data format; and
reading second replacement data for replacing second user data of a
second type ECC block having a second data format by performing the
defect management operation or the LOW operation from the second type ECC
block having the second data format.

[0028]According to an aspect of the present invention, the reproducing of
the ECC blocks further includes reproducing the first replacement data
from a first spare area of the information storage medium and reproducing
the second replacement data from a second spare area that is separate
from the first spare area.

[0029]According to another aspect of the present invention, an apparatus
to reproduce data from an information storage medium including two or
more recording layers to reproduce or record the data by using a same
reproducing and/or recording optical system per layer, includes a
reproducing unit to reproduce the data from the information storage
medium, and a controller to control the reproducing unit to read ECC
blocks from the two or more recording layers by using two or more data
formats used to store user data, and to reproduce the ECC blocks by using
the two or more data formats.

[0030]Additional aspects and/or advantages of the invention will be set
forth in part in the description which follows and, in part, will be
obvious from the description, or may be learned by practice of the
invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0031]These and/or other aspects and advantages of the invention will
become apparent and more readily appreciated from the following
description of the embodiments, taken in conjunction with the
accompanying drawings of which:

[0032]FIG. 1 a diagram to explain a difference in a spot area of each
layer in accordance with different thicknesses of cover layers according
to conventional technology;

[0033]FIG. 2 is a reference diagram illustrating a concept of applying a
different data format to each layer of a multilayer disc having the same
reproducing and/or recording optical system per layer according to an
embodiment of the present invention;

[0034]FIGS. 3A and 3B illustrate two different data formats according to
an embodiment of the present invention;

[0035]FIGS. 4A and 4B illustrate two different data formats according to
another embodiment of the present invention, in which the two data
formats have the same size of additional information and have a different
size of user data;

[0036]FIGS. 5A and 5B illustrate two different data formats according to
another embodiment of the present invention, in which the two data
formats have the same size of user data and have a different size of
additional information;

[0037]FIG. 6 illustrates a multilayer disc having a data area to which a
different data format is applied and a disc management information area
to which the same data format is applied per layer thereof according to
an embodiment of the present invention;

[0038]FIG. 7 illustrates a multilayer disc having original data and
replacement data as a replacement of the original data to which the same
data format is applied when data is replaced by defect management or a
local overwrite (LOW) according to an embodiment of the present
invention;

[0039]FIG. 8 illustrates a six-layer disc to which the embodiment of FIG.
7 is applied according to an embodiment of the present invention;

[0040]FIG. 9 is a schematic block diagram of a recording and/or
reproducing apparatus according to an embodiment of the present
invention;

[0041]FIG. 10 illustrates the thickness of each cover layer of a six-layer
disc according to an embodiment of the present invention;

[0042]FIGS. 11A and 11B illustrate an error correction code (ECC) block 1
for a first data format used to store user data in 128 KB units on the
six-layer disc of FIG. 10 and an ECC block 2 for a second data format
used to store the user data in 136 KB units on the six-layer disc of FIG.
10 according to an embodiment of the present invention;

[0043]FIG. 12 is a flowchart illustrating a method of recording user data
according to an embodiment of the present invention; and

[0044]FIG. 13 is a flowchart illustrating a method of reproducing user
data according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0045]Reference will now be made in detail to the present embodiments of
the present invention, examples of which are illustrated in the
accompanying drawings, wherein like reference numerals refer to the like
elements throughout. The embodiments are described below in order to
explain the present invention by referring to the figures.

[0046]Aspects of the present invention provide a multi data format used
for a multilayer disc having at least two types of data formats, in order
to resolve a problem of a reduction in the data reliability or the disc
capacity since the multilayer disc has a different error influence per
layer due to a defect factor such as dust, fingerprints, scratches,
bubbles, and the like on the disc surface. The multilayer disc according
to aspects of the present invention is compatible with the same
reproducing and/or recording optical system per layer. The reproducing
and/or recording optical system refers to, for example, a recording
and/or reproducing apparatus which uses the same type of reproducing
and/or recording wavelengths or the same number of openings of an object
lens. In other words, the multilayer disc according to aspects of the
present invention does not have a first layer that is a recording layer
according to a first standard, e.g., a BD, and a second layer that is a
recording layer according to a second standard, e.g., a DVD, but instead
has a first layer and a second layer that are recording layers according
to the same standard.

[0047]FIG. 2 is a reference diagram illustrating a concept of applying a
different data format to each layer of a multilayer disc 200 which is
compatible with the same reproducing and/or recording optical system per
layer according to an embodiment of the present invention. Referring to
FIG. 2, a data format 220 having a relatively small proportion of
additional information in relation to user data is applied to a layer 1
having a relatively small error influence due to a defect factor of the
disc surface, whereas a data format 210 having a relatively great
proportion of additional information in relation to user data is applied
to a layer 2 having a relatively great error influence due to the defect
factor of the disc surface. Therefore, a space to guarantee data
reliability of the multilayer disc and to record the greatest amount of
user data is secured when the multilayer disc is reproduced. According to
an aspect of the present invention, the additional information comprises
parity information. However, the additional information is not limited to
being parity information in other aspects, and may instead be other types
of information used to record and/or reproduce the user data, such as
sync information, address information, or any combination of these three
types of information.

[0048]A method of determining a relatively small or great proportion of
additional information in relation to the user data will now be
described.

[0049]FIGS. 3A and 3B illustrate two different data formats according to
an embodiment of the present invention. Referring to FIGS. 3A and 3B, a
first data format 310 and a second data format 320 have the same size of
data including user data and additional information. The first data
format 310 has a relatively great proportion of additional information in
relation to the user data compared to the second data format 320. The
second data format 320 has a relatively small proportion of additional
information in relation to the user data compared to the first data
format 310. The data reliability of the first data format 310 having the
relatively great proportion of additional information in relation to the
user data is higher than that of the second data format 320.

[0050]FIGS. 4A and 4B illustrate two different data formats 410 and 420
according to another embodiment of the present invention, in which each
of the two data formats 410 and 420 have the same size of additional
information and have a different size of user data. That is, the two data
formats 410 and 420 each have a relatively small or great proportion of
additional information in relation to the user data by allowing the two
data formats 410 and 420 to have the same size of additional information
and adjusting the size of the user data that is to be stored therein.

[0051]Referring to FIGS. 4A and 4B, the size of additional information 412
of a first data format 410 is the same as the size of additional
information 422 of a second data format 420, whereas the size of user
data 411 of the first data format 410 is different than that of the size
of user data 421 of the second data format 420. Since the size of the
additional information 412 is the same as the size of the additional
information 422 and the size of the user data 411 is smaller than the
size of the user data 421, the encoding reliability of the first data
format 410 is higher than the encoding reliability of the second data
format 420.

[0052]FIGS. 5A and 5B illustrate two different data formats 510 and 520
according to another embodiment of the present invention, in which the
two data formats 510 and 520 have the same size of user data and have a
different size of additional information. That is, the two data formats
510 and 520 have a relatively small or great proportion of additional
information in relation to the user data by allowing the two data formats
510 and 520 to have the same size of user data that is to be stored
therein and adjusting the size of the additional information thereof.

[0053]Referring to FIGS. 5A and 5B, the size of additional information 512
of a first data format 510 is different than that of the size of
additional information 522 of a second data format 520, whereas the size
of user data 511 of the first data format 510 is the same as the size of
user data 521 of the second data format 420. Since the size of the user
data 521 is the same as the size of the user data 511, and the size of
the additional information 522 is greater than the size of the additional
information 512, the encoding reliability of the first data format 510 is
higher than the size of the second data format 520.

[0054]In addition to the data formats of FIGS. 3A, 3B, 4A, 4B, 5A, and 5B,
there is a method of varying the length of an error correction code (ECC)
word to error-correct user data of a data format. Although additional
information is added to user data in the same ratio, the longer the error
correction code word is, the more the error correction performance
increases.

[0055]Although data is conventionally recorded onto a multilayer disc
using a different data format per layer, in order to reduce complexity
associated with performing data operations on a disc having a multi data
format, aspects of the present invention provide data, which is recorded
onto a disc management information area used to record information
regarding disc recording and/or reproducing management operations, having
the same data format irrespective of layers, making it easier to operate
the multilayer disc.

[0056]FIG. 6 illustrates a multilayer disc 200 having a data area on which
a different data format is applied per layer thereof and a disc
management information area on which the same data format is applied per
layer thereof according to an embodiment of the present invention.
Referring to FIG. 6, the multilayer disc 200 comprises a layer 1 and a
layer 2 each having a lead-in area 210, a data area 220, and a lead-out
area 230. The lead-in area 210 of the layers 1 and 2 includes a disc
management information area 211. Although data is recorded onto the data
area 220 of the layer 1 by using a second data format and onto the data
area 220 of the layer 2 by using a first data format, the data is
recorded on the disc management information area 211 included in the
lead-in area 210 of the layers 1 and 2 by using a single data format,
e.g., the first data format. This is because it is a frequent occurrence
that when a recording and/or reproducing apparatus uses disc management
information, the recording and/or reproducing apparatus continuously
records and/or reproduces disc management information of the disc
management information area 211 of the layers 1 and 2, or manages a
combination of the disc management information of the disc management
information area 211 of the layers and 1 and 2.

[0057]FIG. 7 illustrates a multilayer disc 200 having original data and
replacement data as a replacement of the original data to which the same
data format is applied when data is replaced by defect management or a
local overwrite (LOW) according to an embodiment of the present
invention. When data is "replaced by defect management," this phrase
refers to replacement data as a replacement of the defective data being
recorded onto another area of the disc when a defect is detected from
data recorded onto a predetermined area of a disc. When data is "replaced
by the LOW," this phrase refers to when updated replacement data is
recorded onto another area of a disc in order to update data recorded on
a predetermined area of the disc. When data is replaced by defect
management operation or the LOW, an application of the same data format
to the original data and the replacement data makes it possible to easily
manage the data.

[0058]Referring to FIG. 7, replacement data 720 as a replacement of
original data 710 recorded onto a layer 2 of the multilayer disc 200 by
the defect management or the LOW using a first data format is recorded
onto the layer 2 by using the first data format. Replacement data 740 as
a replacement of original data 730 recorded onto a layer 1 of the
multilayer disc 200 by the defect management or the LOW by using a second
data format is recorded onto the layer 2 by using the second data format.

[0059]FIG. 8 illustrates a six-layer disc 201 to which the embodiment of
FIG. 7 is applied according to an embodiment of the present invention.
Referring to FIG. 8, data is recorded onto the six-layer disc using two
data formats. When the data is recorded onto layers 1, 2, and 3 by using
a second data format, and onto layers 4, 5, and 6 by using a first data
format, replacement data due to a defect occurring in one or more of the
layers 1, 2, or 3 or by the LOW is recorded onto the one or more of the
layers 1, 2, or 3, and replacement data which is recorded due to a defect
occurring in one or more of the layers 4, 5, or 6 or by the LOW is
recorded onto one or more of the layers 4, 5, or 6. It is understood that
aspects of the present invention may be employed with optical discs
having more or less than six layers.

[0060]In more detail, replacement data A' due to a defect in original data
A recorded onto the layer 6 or by the LOW is recorded onto the layer 5,
and replacement data B' due to a defect with original data B recorded
onto the layer 1 or by the LOW is recorded onto the layer 3. However,
aspects of the present invention are not limited thereto. Replacement
data A' due to the defect with original data A recorded onto the layer 6
or by the LOW is recorded onto the layer 4 or 6. Replacement data B' due
to the defect with original data B recorded onto the layer 1 or by the
LOW is recorded onto the layer 3.

[0061]Since the data is recorded onto the layers 1, 2, and 3 and onto the
layers 4, 5, and 6 by using a different data format, the data is easily
managed by recording replacement data as a replacement of the data onto a
layer by using the same data format.

[0062]FIG. 9 is a schematic block diagram of a recording and/or
reproducing apparatus 900 according to an embodiment of the present
invention. Referring to FIG. 9, the recording and/or reproducing
apparatus 900 which records and/or reproduces data includes a recording
and/or reproducing unit 920 and a controller 910. The recording and/or
reproducing unit 920 records the data onto an information storage medium,
e.g., a disc 200 in which the same reproducing and/or recording optical
system is used per layer, according to the control of the controller 910
and reproduces data in order to reproduce the data recorded onto the disc
200. The controller 910 controls the recording and/or reproducing unit
920 to record and/or reproduce data and performs signal processing on the
data to be recorded and on the reproduced data.

[0063]In particular, the controller 910 controls the recording and/or
reproducing unit 910 to record ECC blocks having at least two data
formats to store user data onto a different recording layer of the
information storage medium, or processes the data reproduced by the
recording and/or reproducing unit 920, and obtains valid data.

[0064]Furthermore, according to an aspect of the present invention, the
controller 910 controls the recording and/or reproducing unit 920 to
record an ECC block onto a recording layer having a thick cover layer by
using a data format which is relatively low in terms of error correction
performance, and to record an ECC block onto a recording layer having a
thin cover layer by using a data format which is relatively high in terms
of error correction performance.

[0065]When each recording layer of the disc 200 includes a disc management
information area, the controller 910 controls the recording and/or
reading unit 920 to record ECC blocks onto the disc management
information area of each recording layer by using the same data format.
According to an aspect of the present invention, the controller 910
controls the recording and/or reproducing unit 920 to record first
replacement data by defect management of first user data recorded onto an
ECC block by using a first data format or by the LOW onto an ECC block
using the first data format, and to record second replacement data by
defect management of second user data recorded onto an ECC block by using
a second data format or by the LOW onto an ECC block by using the second
data format.

[0066]The controller 910 controls the recording and/or reproducing unit
920 to record the first replacement data onto a first spare area and to
record the second replacement data onto a second spare area that is
separate from the first spare area. It is understood that the first and
second spare areas may be located in various places throughout the disc
200, such as the lead-in area 210 or the data area 220 (FIG. 6).

[0067]The recording and/or reproducing unit 920 includes a pickup. The
disc 200 is installed in the pickup. The pickup emits or receives a light
to transfer data with respect to the disc 200. The controller 910
comprises a host interface (I/F) 911, a digital signal processor (DSP)
912, a radio frequency (RF) amplifier (AMP) 913, a servo 914, and a
system controller 915.

[0068]The host 930 receives a data recording and/or reproducing
instruction from a user and transfers the data recording and/or
reproducing instruction to the recording and/or reproducing apparatus 900
through the host I/F 911. The host I/F 911 interfaces with the host 930
and the recording and/or reproducing apparatus 900. The system controller
915 determines a data format of data according to the data recording
and/or reproducing instruction received from the host 930 and controls a
data formatter/deformatter 916 of the DSP 912 to encode data to be
recorded by using the determined data format.

[0069]In particular, the DSP 912 includes the data formatter/deformatter
916 which includes at least two data formats. The data
formatter/deformatter 916 ECC encodes the user data by using an ECC block
that is to be recorded onto each recording layer according to the control
of the system controller 915, inserts an error detection code (EDC),
address information, etc. in the encoded user data, and applies data
formats appropriate to the recording layers to the user data. The DSP 912
modulates the user data having the data formats, inserts a sync pattern
into the user data at a predetermined period, and forms recording unit
blocks. The RF AMP 913 changes the user data that is output from the DSP
912 into RF signals. The pickup 920 records the RF signals that are
output from the RF AMP 913 onto the disc 200. The servo 914 receives an
instruction necessary for a servo control from the system controller 915
and servo-controls the pickup 920.

[0070]The host I/F 911 receives a reproduction instruction from the host
930 when the user data is reproduced. The system controller 915 performs
initialization necessary for the reproduction of the user data.

[0071]The system controller 915 controls the recording and/or reproducing
unit 920 to reproduce recording management data that is recorded onto a
predetermined area of the disc 200. In particular, according to an aspect
of the present invention, the system controller 915 controls the
recording and/or reproducing unit 920 to reproduce ECC blocks having at
least two data formats to store the user data from a different recording
layer of the disc 200. The system controller 915 controls the recording
and/or reproducing unit 920 to reproduce the ECC block from the recording
layer having the thick cover layer by using the data format which is
relatively low in terms of error correction performance, and to reproduce
the ECC block from the recording layer having the thin cover layer using
the data format which is relatively high in terms of error correction
performance.

[0072]According to an aspect of the present invention, when each recording
layer of the disc 200 includes the disc management information area, the
system controller 915 controls the recording and/or reproducing unit 920
to reproduce ECC blocks from the disc management information area of each
recording layer by using the same data format. However, it is understood
that the disc 200 is not required to have a disc management information
area in each recording layer according to other aspects of the present
invention.

[0073]The pickup 920 irradiates a laser beam onto the disc 200, receives
the reflected laser beam from the disc 200, and outputs an optical
signal. The RF AMP 913 changes the optical signal that is output from the
pickup 920 into an RF signal, provides the DSP 912 with modulated data
that is obtained from the RF signal, and provides the servo 914 with a
control servo signal obtained from the RF signal. The DSP 912 demodulates
the modulated data and outputs data that is ECC error corrected. In
particular, the data formatter/deformatter 916 of the DSP 912 receives a
determination signal indicating a recording layer from which data to be
decoded is read, for example, whether to deformat the data by using a
first data format or a second data format, from the system controller
915, and decodes the data to be decoded according to the determination
signal. According to an aspect of the present invention, the data
formatter/deformatter 916 decodes the first replacement data of the first
user data recorded onto the ECC block by using the first data format or
by the LOW by using the first data format, and decodes the second
replacement data of the second user data recorded onto the ECC block by
using the second data format or by the LOW by using the second data
format.

[0074]Meanwhile, the servo 914 receives the servo signal from the RF AMP
913 and the instructions necessary for the servo control from the system
controller 915, and performs a servo control operation for the pickup
920. The host I/F 911 sends the data received from the DSP 912 to the
host 930.

[0075]FIG. 10 illustrates the thickness of each cover layer of a six-layer
disc, such as, for example, the six-layer disc 201 shown in FIG. 8,
according to an embodiment of the present invention. Referring to FIG.
10, the thickness of each cover layer of layers 1, 2, 3, 4, 5, and 6 of
the six-layer disc is 100 μm, 90 μm, 80 μm, 70 m, 60 μm, and
50 μm, respectively. It is understood, however, that aspects of the
present invention can be implemented in six-layer discs having cover
layers with different thicknesses from those shown in FIG. 10.

[0076]FIGS. 11A and 11B respectively illustrate an ECC block 1 for a first
data format used to store user data in 128 KB units on the six-layer disc
201 of FIG. 10 and an ECC block 2 for a second data format used to store
the user data in 136 KB units on the six-layer disc 201 of FIG. 10
according to an embodiment of the present invention.

[0077]Table 1 shows values of an optical system specification applied to
the present embodiment.

[0078]FIG. 11A is a diagram of the structure of the ECC block 1 for the
first data format used to store user data in 128 KB units on the
six-layer disc 201. FIG. 11B is a diagram of the structure of the ECC
block 2 for the second data format used to store the user data in 136 KB
units on the six-layer disc 201.

[0079]Referring to FIGS. 11A and 11B, the size of the ECC blocks 1 and 2
is 248×640. The same size of the ECC blocks 1 and 2 makes it
possible to resolve the complexity associated with conventional
operations of using two ECC blocks with different sizes by using the same
recording unit format that is converted into substantial recording units
by modulation, addition of a sync pattern, etc., in order to record the
user data onto a substantial information storage medium. Both
reed-solomon (RS) and low-density parity check (LDPC) codes can be
applied to the ECC blocks 1 and 2 as ECC codes according to aspects of
the present invention. It is understood that either RS or LDPC codes can
be applied to one or both of the ECC blocks 1 and 2, or that a
combination of both the RS and LDPC codes can be applied to one or both
of the ECC blocks 1 and 2. 640 RS codes (248,208) are applied to the ECC
block 1 and 640 RS codes (248,216) are applied to the ECC block 2. The
ECC blocks 1 and 2 are interleaved, respectively, and then modulated
using a recording modulation code. The sync pattern is inserted into the
modulated ECC blocks 1 and 2 at a predetermined period. The recording
unit blocks formed as such are recorded onto the information storage
medium 201. The recording unit block formed by the ECC block 1 is
recorded onto the layers 4, 5, and 6 which are relatively more influenced
by a defect factor, whereas the recording unit block formed by the ECC
block 2 is recorded onto the layers 1, 2, and 3 which are relatively less
influenced by the defect factor. It is understood that the ECC blocks 1
and 2 are not limited to being applied to an equal number of layers, for
example, the ECC block 1 may be recorded only on layer 6, and the ECC
block 2 may be recorded on the remaining layers 1-5.

[0080]FIG. 12 is a flowchart illustrating a method of recording user data
according to an embodiment of the present invention. Referring to FIG.
12, a recording and/or reproducing apparatus, such as, for example, the
recording and/or reproducing apparatus 900 shown in FIG. 9, receives a
recording instruction from the host 930 at operation 1210. In more
detail, the host 930 sends the recording instruction, user data that is
to be recorded, and a logical sector number on which the user data is to
be recorded to the recording and/or reproducing apparatus 900. The host
I/F 911 converts the local sector number into a physical sector number
according to the recording instruction received from the host 930.

[0081]The recording and/or reproducing apparatus 900 encodes the user data
by using a data format appropriate to a layer on which the user data is
to be recorded at operation 1220. In more detail, the system controller
915 sends an instruction to the data formatter 916 to form the data
format appropriate to the layer corresponding to the physical sector
number. The data formatter 916 ECC encodes the user data by using an ECC
block having the data format appropriate to the layer according to the
control of the system controller 915, inserts an error detection code
(EDC), address information, etc. into the user data, and forms the data
format. The DSP 912 modulates the data format, inserts a sync pattern
into the data format at a predetermined period, forms a recording unit
block, and provides the RF AMP 913 with the recording unit block. The RF
AMP 913 generates a recording pulse suitable for the recording unit block
and transmits the recording pulse to the pickup 920.

[0082]The recording and/or reproducing apparatus 900 records the encoded
user data onto a disc at operation 1230. In more detail, the servo 914
controls the pickup 920 to move to a disc position corresponding to the
physical sector number onto which the user data is to be recorded
according to the instruction of the system controller 915. The pickup 920
adjusts the amount of light according to the recording pulse and records
the user data on a recording layer.

[0083]FIG. 13 is a flowchart illustrating a method of reproducing user
data according to an embodiment of the present invention. Referring to
FIG. 13, a recording and/or reproducing apparatus receives a reproduction
instruction from the host 930 at operation 1310. In more detail, the host
930 transmits the reproduction instruction and a logical sector number of
user data that is to be reproduced to the recording and/or reproducing
apparatus 900, and an interface converts the logical sector number
according to the reproduction instruction into a physical sector number.

[0084]The recording and/or reproducing apparatus reproduces the user data
from a disc according to the reproduction instruction at operation 1320.

[0085]The system controller 915 searches for a layer corresponding to the
physical sector number, and instructs the servo 914 to find a position
corresponding to the physical sector number. The servo 914 controls the
pickup 920 to move to the position corresponding to the physical sector
number. The pickup 920 reproduces the user data from the physical sector
number and transmits the user data to the RF AMP 913. The RF AMP 913
converts a signal reproduced from the pickup 920 into RF data and
transmits the RF data to the DSP 912.

[0086]The recording and/or reproducing apparatus 900 decodes the
reproduced user data using a data format used for the reproduced layer at
operation 1330. In more detail, the DSP 912 performs signal processing
with regard to the RF data and transmits the RF data to the data
formatter 916. The data formatter 916 ECC decodes the RF data. At this
time, the system controller 915 controls the data formatter 916 to decode
the user data by using the data format used for the reproduced layer. The
data formatter 916 decodes the user data using the data format used for
the reproduced layer according to the control of the system controller
915, and transmits the decoded user data to the host 930 through the host
I/F 911.

[0087]Aspects of the present invention can also be embodied as computer
readable codes on a computer readable recording medium. The computer
readable recording medium is any data storage device that can store data
which can be thereafter read by a computer system. Examples of the
computer readable recording medium include read-only memory (ROM),
random-access memory (RAM), CD-ROMs, magnetic tapes, floppy disks, and
optical data storage devices. The computer readable recording medium can
also be distributed over network coupled computer systems so that the
computer readable code is stored and executed in a distributed fashion.
Also, functional programs, codes, and code segments for accomplishing
aspects of the present invention can be easily construed by programmers
of ordinary skill in the art to which the present invention pertains.

[0088]As described above, aspects of the present invention record and
reproduce user data by using a plurality of multi data formats in order
to reduce a drop in data reliability or a reduction in data capacity due
to variations in signal quality of each layer of a multilayer information
storage medium that uses the same reproducing and/or recording optical
system per layer, thereby guaranteeing data reliability and increasing
storage capacity.

[0089]Although a few embodiments of the present invention have been shown
and described, it would be appreciated by those skilled in the art that
changes may be made in this embodiment without departing from the
principles and spirit of the invention, the scope of which is defined in
the claims and their equivalents.